The Cardinals, 54-48 as of Friday night, are in need of a catcher. Yadier Molina recently had surgery to repair a torn ligament on his thumb and isn't expected to return until at least mid-September.

Pierzynski, 37, signed a one-year deal with the Red Sox this off-season for $8.25 million and was expected to add a significant chunk of offense from the left side of the plate. But he hit just .254 with a .633 OPS in 72 games while playing below-average defense before the Red Sox released him.

"The offense wasn’t there," general manager Ben Cherington said when Pierzynski was designated for assignment. "I'm not trying to be critical of him. It wasn’t any lack of effort on his part. It just wasn’t there. When you sign A.J. Pierzynski, that’s what you're hoping: You're hoping for left-hand offense at a premium position, and we thought that was important to the team. If we got that, it would complement the team."